• Journal of Korean Society of Steel Construction
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• v.19 no.3
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• pp.271-280
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• 2007

This paper presents the results of an experimental study to evaluate the redundancy in two plate-girder bridges, which are generally classified as non-redundant load path structures. The study was performed at a time when one of the two girders was damaged. The bottom lateral bracing was considered the experimental variable, and two 1/5-scale bridge specimens of simple span with and without a lateral bracing system were fabricated. Loading tests were first performed on the intact specimens without a cracked girder, within an elastic range. Thereafter, the ultimate loading tests were conducted on the damaged specimens with an induced crack at the center of a girder. The test results showed that the cross beams and the concrete deck redistributed some of the load to the uncracked girder, but the lateral bracing system played an important role in improving the redundancy during the damage and was also effective for load redistribution even when the bridge was intact.

• Journal of the Korean Vacuum Society
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• v.19 no.5
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• pp.331-340
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• 2010

3D fluid based numerical modelling is done for a VHF multi hollow cathode array plasma enhanced chemical vapor deposition system. In order to understand the fundamental characteristics of it, Ar plasma is analyzed with a condition of 40 MHz, 100 Vrf and 1 Torr. For hole array of 6 mm diameter and 20 mm inter-hole distance, plasma is well confined within the hole at an electrode gap of 10 mm. The peak plasma density was $5{\times}10^{11}#/cm^3$ at the center of the hole. When the substrate was assumed at ground potential, electron temperature showed a peak at the vicinity of the grounded walls including the substrate and chamber walls. The reaction rate of metastable based two step ionization was 10 times higher than the direct electron impact ionization at this condition. For $H_2$, the spatial localization of discharge is harder to get than Ar due to various pathways of electron impact reactions other than ionization.

• Journal of the Korean Society for Library and Information Science
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• v.45 no.3
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• pp.27-47
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• 2011

The purpose of this study is to propose the direction of developing a new information portal for the disabled by examining the general characteristics, services, resources, and external links of five domestic and foreign information portals for the disabled, and 104 websites of organizations and institutions for the disabled in Korea. Information portals for the disabled examined in this study include the 'Bokjiro' portal and Dibrary Disability portal in Korea, the NARIC portal in the U.S.A., the National Accessibility Portal of the Republic of South Africa, and the National Interactive Portal of India. The following were proposed: (1) Consider both the disabled and the general public as potential users, (2) Identify the specific subject categories appropriate for their needs, (3) Secure information from high quality information sources, (4) Provide the communication and participation channel for the disabled, and (5) Observe Web Accessibility Standards.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12A
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• pp.1191-1199
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• 2008

We propose the Staggered-zone Resource Allocation (SRA) in order to relax throughput decrease problems by the co-channel interference of the cell boundary users at the cellular OFDMA system using frequency reuse factor K=1 and analyze the throughput improvement. The proposed algorithm allocates the resources to the users in compliance with resource allocation rule which is planned in order to minimize co-channel interference between cells without any additional information. The resource allocation method in the SRA lines up the users in pathloss order as descending series, and then allocates from pre-determined resource allocation region where decides differently in each cell. This algorithm prevents the co-channel interferences of the cell boundary user to be caused by using same resource simultaneously and equalizes interference to the users in the cell.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9A
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• pp.1395-1404
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• 2000

In this paper, we propose a heuristic wavelength routing algorithm for IP datagrams in WDM (Wavelength-Division Multiplexing) networks which operates in a distributed manner, while most previous works have focused centralized algorithms. We first present an efficient construction method for a loose virtual topology with a connectivity property, which reserves a few wavelength to cope with dynamic traffic demands properly. This connectivity property assures that data from any source node could reach any destination node by hopping one or multiple lightpaths. We then develop a high-speed distributed wavelength routing algorithm adaptive to dynamic traffic demands by using such a loose virtual topology and derive the general bounds on average utilization in the distributed wavelength routing algorithms. Finally, we show that the performance of the proposed algorithms is better than that of the FSP(Fixed Shortest-Path) wavelength routing algorithms through simulation using the NSFNET[1] and a dynamic hot-spot traffic model, and that the algorithms is a good candidate in distributed WDM networks in terms of the blocking performance, the control traffic overhead, and the computation complexity.

• Korean Journal of Social Welfare Studies
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• v.44 no.3
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• pp.323-346
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• 2013

The main purpose of this study is to analyze job sequences according to poverty profiles that the working poor have had. For the stated purpose, this study examines characteristics and patterns of job sequences by diving the subgroups, using the 10 year data of KLIPS and the sequence analysis. Major findings are as follows. The working-transient poor have different characteristics, such as longer working term, less job change, less number of gap and length, and relatively higher monthly income, from the working-recurrent poor and the working-persistent poor. However, there are no different characteristics between the working-recurrent poor and working-persistent poor, except for monthly income. Job sequences are divided into 5 clusters and job sequences types according to the working poor subgroups are quite different. Such analysis results would contribute to planning poverty policies based on job sequences differently seen in subgroups and finding specific policy alternatives to relieve the working poor.

• International Area Studies Review
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• v.13 no.3
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• pp.51-71
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• 2009

We pursue empirically influential determinants of risk-sharing across various groups in the United States. We consider all the possible combinations out of the eight BEA economic regions and relate the risk-sharing measure for each group to sectoral composition difference under the control of the state-level macroeconomic and financial characteristics. Our results show that more active risk-sharing via cross-ownership market is observed in groups exhibiting more different sectoral composition. The evidence implies that, given other economic and financial conditions equal, economic union tends to share more consumption risk among its members that are more heterogeneous in their sectoral composition. These days, many countries aim to form FTA and other forms of economic integration. We suggest that they should pay attention to sectoral composition for member countries to minimizes income shock in the integrated economy.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.192-209
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• 2014

The important national cultural heritages were retrieved. April 25 2014, US President Barack Obama formally returned 9 Seals of Joseon Dynasty and Korean Empire in Korea-US Summit taken place in Cheong Wa Dae. These Seals were taken out of Deoksugung illegally by a US Marine Corps officer during Korean War, handed down to his posterity, and last November 2013 confiscated by HSI in San Diego. Through investigations above facts turned out and it was decided to return these relics to Koera. In the process of surveying these seals, I confimed the authenticity of them and transferred my opinion to Cultural Heritage Administration. In this paper, I try to summarize the historical value of each Seals and suggest the remaining task.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.35-35
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• 2021

최근 우리나라는 기후변화로 인한 이상기후 현상으로 호우 및 홍수 등에 의한 수재해를 예방하기 위한 설계빈도 적용방안 개발이 필요하다. 과거 지방하천의 일률적인 설계빈도의 적용 및 간접·주관적인 하천의 중요도와 지역특성에 대한 등급의 결정은 하천사업의 효율적 관리와 수행에 있어서 저해요소로 작용되어 왔다. 또한, 미래 기후변화 시나리오에 따라 하천의 중요도 및 계획 규모가 적절히 적용되어야 한다. 본 연구는 충청남도의 492개 지방하천에 대하여 유역특성(유역면적, 형상계수), 하천특성(하도경사, 수계 및 하천차수, 배수영향 구간), 이상강우 특성(이상강우 발생빈도, 시가화 침수면적)에 대한 현재 설계빈도에 대한 적절성을 평가하였다. 설계빈도에 대한 정량적 추정은 베이즈 이론을 활용하여 가중치를 산정한 후 최적분포형을 선정하였다. 최적분포형의 중앙값을 일반적인 지방하천의 설계빈도인 80년 빈도로 설정하고 상·하위 0.5%가 각각 100년, 50년 빈도로 가정하여 492개 지방하천을 평가하였다. 이상강우의 발생빈도와 시가화 침수면적에 따라 하천의 설계빈도가 높게 산정되는 것으로 분석되었다. 미래 기후변화 시나리오를 적용할 경우 현재 설계빈도(설계수명)에 대한 시나리오별 미래 재현기간을 산정하여 미래 설계빈도에 대한 위험도를 평가하였다. 13개 기후변화 시나리오의 대표농도경로 4.5와 8.5를 분석한 결과, 평균 3.2%, 12.8%의 위험도가 증가하는 것으로 분석되었다. 본 연구결과는 객관적인 지방하천의 적정 설계빈도 결정방안을 제시하였으며, 미래 계획홍수량 증가로 인하여 효율적인 토지이용이 제한될 것으로 예상됨에 따라 하천사업의 예산절감 및 우선순위 결정 등에 활용 가능할 것으로 판단된다.

• 한국노년학
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• v.31 no.2
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• pp.407-418
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• 2011

This study aim to examine effects of physical, psychological, social factors on elder's life satisfaction from KLIPS(Korea Labor & Institute Panel Study)'s data. Subjects were 4,032(men 1696, women 2336) aged 65 over. Physical factors include subjective physical health condition and ADL(Activities of daily living). Psychological factors include subjective emotional difficulty and depression(ces-d). Social factors include 7 meetings. Major findings in this study are follows. First, physical, psychological factors were a significant effects on elder's life satisfaction. But, in social factors, religious meeting, friendship meeting, leisure meeting, volunteer meeting were significant factors exclude reunion meeting, political meeting, etcetera meeting. Second, mediations of ADL, subjective emotional difficulties, and social participations were significant factors.